In wireless communication systems such as spread spectrum cellular communication systems, cross-correlators may be used to perform cross correlation between streams of sequences of spread spectrum signals. For example, in cellular wideband code division multiple access (WCDMA) systems a spread spectrum signal may include a coding sequence, for example, a pseudo-random code. In cellular wideband code division multiple access (WCDMA) systems, the pseudo-random code may be an M-sequence or a Gold Sequence which has good “noise like” properties and is simple to construct. Furthermore, the sequences of the spread spectrum signal may be the product of a 64 chip Walsh code (aimed at separating up to 64 different users per base) and a periodic pseudorandom noise (PN) sequence (aimed at separating the different bases).
Cross-correlators may be used to perform cross-correlation between the streams of sequences. However, existing hardware implementations of cross-correlators may include a large number of components and may consume large currents.
Thus, there is a need for hardware and/or software implementations for calculating cross-correlation values to mitigate the above-described disadvantages.
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